In
chemistry,
pyran, or
oxine, is a six-membered
heterocyclic, non-aromatic ring, consisting of five
carbon atoms and one
oxygen atom and containing two
double bonds. The
molecular formula is C
5H
6O. There are two
isomers of pyran that differ by the location of the double bonds. In
2H-pyran, the saturated carbon is at position 2, whereas, in
4H-pyran, the saturated carbon is at position 4.